It appears you're interested in specifications for the Yamaha YFZ450X SE. This ATV model is powered by a Single cylinder, four-stroke engine with 449.00 ccm (27.40 cubic inches) of actual displacement before 11.6:1 compression. Fueling is metered via Injection. Yamaha Fuel Injection (YFI), 42mm allowing this machine to produce its horsepower and torque. According to our records engine heat of the Yamaha YFZ450X SE is moderated by Liquid. You'll need to get familiar with the 5-speed transmission and pay attention to final drive Chain maintainence. Our best information shows that the front tire size is 21/7-10 and the rear is 20/10-9 . The entire package is supported by the frame, . We know you like to go fast or cruise all day, but when you need to stop, you'll be dependant on Double disc front brakes and Single disc rear brakes. The Yamaha YFZ450X SE was launched in 2011, and we're happy to know (or assume) you've got one in your garage. To help you keep your ride in tip-top shape, consider purchasing an owner or service manual.